2008 Annual Meeting
(772f) Modeling the Phase Behavior of Polydisperse Rodlike Molecules with Attractive Interactions
Authors
We show that the resulting phase diagram can capture the phase behavior of experimental systems featuring rods with attractive interactions simply by fitting the adjustable parameters of the square-well potential. Specifically, we show that the model closely replicates experimental data points for isotropic/liquid crystalline phase separation of single-walled carbon nanotubes (SWNTs) in various super-acids. The model predicts that the isotropic cloud point goes to zero at a certain solvent quality, and this prediction was subsequently confirmed by experiments. This result means that for acids below a threshhold acid strength, the liquid-crystalline phase is present even at dilute concentrations. The model yields critical insights into both the fundamental thermodynamics as well as practical applications of SWNT/super-acid systems.